In recent years, the use of mobile devices such as smartphones, personal digital assistants (PDAs), tablet computers, and laptop computers has become widespread. These devices allow users to perform a variety of functions such as browsing the Internet, taking pictures or videos, making phone or video calls, etc. In addition, such devices often provide applications with various functionalities.
Further, many such mobile devices may include one or more microphones that are used to capture audio signals. Some of these devices may allow audio signals to be captured and processed for voice activation. Using such voice activation feature, an application may be activated by inputting a voice keyword in the mobile devices.
In order to take full advantage of such voice activation feature, a mobile device typically needs to be configured to continuously monitor and process environmental sounds for a potential keyword. However, the continuous operation of the voice activation feature may deplete the limited power resources of the mobile device.